If California left, where would its seats go?

[Dr. MB]

The Democratic Party would no doubt get more conservative, maybe not on economics but would probably move toward a pro-gun position and abandon other policies mainly driven by the urban California liberals. I could see them picking up some more rural midwestern and New York seats and I don't think the image would be as tainted now among white southerners.

[Dr. MB]

I don't see Idaho or Utah's new districts being R. Boise and SLC could force at least one of their states' districts to be D.

Ada County is neither liberal enough (voted 48-39 Trump-Clinton, 54-42 Romney-Obama) nor large enough (only about 400k, needs more than 500k) to sustain a district.

Utah is possible, it would be D plus a few points but wouldn't be a completely solid seat. Idaho with 2 districts is physically impossible, you can make one that leans R a bit but even if you combine literally all Democratic precincts in the state (mostly in Boise, Pocatello, and Moscow area), that's still not enough to create a majority-D seat.